I have a self-installed Leviton TTI06-1LM dimmer (600w capacity) that controls a halogen light that uses 12x 12v/20w (140w total) halogen lights. The dimmer works fine, but once a day, or perhaps every other day, it stops working and we must reset the breaker. There are other lights on the same circuit that are not impacted. It's just the dimmer that fails. Any suggestions?

No, Dimmers are basically resistance devices. The max load on them is not at full brightness anyway.

If you have determined the wiring to be correct, then yes, the remote is probably defective..

According to Lightolier literature, your Lightolier OS600 is called a "strap dimmer". Having 540W on a 600w rated switch is pretty close to the limit (90%) of the switch, and will cause the switch to fail sooner than say a 300w load. The 600w rating of the switch applies only if all the heating sink fins are in place. Often times, when installing in a box with another switch or dimmer, fins must be removed to allow the switch to physically fit. If any fins are removed, the rating of the switch is reduced. Page 30 of the manual shows that a 600w strap dimmer that has a single fine removed is reduced to a 500w capacity dimmer, and if both fins are removed, it is reduced to a 400w dimmer. You may find that you will need a 1000w dimmer to reliably gain control of your 540w load, as it will control 600w even with both fins removed. This derating is required due to the heat created by the dimmer. Heat is a killer for electronics, and solid state dimmers are no exception.

Check out page 32 of that manual. On it, are wiring diagrams for dimmers and switches. I believe your is figure "G" that shows the 120v "hot" (black) connected to the black wire of ALL switches, the yellow wires of ALL the switches are connected together, but are not connected to anything else, the 120v neutral (white) connects to the MASTER white wire AND light fixture white wire and finally, the MASTER red wire connects to the light fixture black wire.

It is also important to note that these switches are for standard tungsten incandescent and quartz halogen lamps ONLY. They are NOT suitable for CFL, Fluorescent or other types frequently found in commercial / industrial buildings such as neon or other gas lamps such as Metal Halide, Mercury Vapor, High Pressure Sodium, etc.

I hope this helps & good luck!

It's not quite that simple..

According to the manual for your switch, it is stated "Use with magnetic low-voltage transformers, incandescent, or 120V halogen fixtures only." Also, there is a minimum load of 40W or 40VA. Your LED lamp load will need to satisfy BOTH of these requirements. Electronic circuits are not to be "dimmed" with this dimmer - but use of either the VZE04-1L (400W max) or VZE06-1L (600W max) is supported.

You will need to provide the manufacturer and model number of the LED lamp(s) to be dimmed by this switch. Or, you can use traditional dimmers (if desired) with LED lamps that are specifically labeled as "dimmable" on their packaging.

Once the lamp model is known it will be possible to learn about their dimability assuming that they are not cheap imports with no real customer support contacts. Name brand lamps will have this support, and you can even call them yourself and inquire directly about the suitability to task for the dimmer. If the lam company doesn't know about the switch, contact Leviton with the lamp info at Customer Service: 1-800-323-8920 • FAX: 1-800-832-9538 Tech Line: 1-800-824-3005

Good luck!

Unfortunately with the new electronics, there is not much to do when they go bad. Sometimes they go out and nothing works, sometimes just no dimming. I have had it where I got careless installing one live, and hit the hot to the frame. Worked fine as a switch, but no dimming! Best to replace it.

are you using one of those florescent bulbs? They generally can't be dimmed.

There are no repair parts for in-wall electrical devices.
When they go dad you buy another.
Lowes and Home Depot carry inexpensive dimmers.
Look for 3 things:
1) Wattage: most off-the-shelf dimmers are 500-1000Watts. Add up total wattage.
2) If you are dimming incandescent bulbs, dimmer package will say tungsten or incandescent.
Package will say florescent if dimmer also works for florescent bulbs.
3) If dimmer is 3-way, with a dimmer on either end of a room, many times the dimmers are sold as a package of 2 dimmers with 1 dimmer that controls the other dimmer.

Lutron dimmers
http://www.lutron.com/Products/StandAloneControls/Dimmers-Switches/Pages/DimmersSwitches.aspx
Leviton dimmers
http://www.leviton.com/OA_HTML/ibeCCtpSctDspRte.jsp?section=15265&minisite=10025

This, unfortuantely, is one of the usual challenges associated with dimming. The buzzing usually gets worse at around the 1/2 light level point. I don't think the issue has to do with whether the lamp is halogen, but rather how the lamp is physically constructed - and that differs from manufacturer to manufacturer. Long story short, I would take note of the lamps you purchased, and when replaced, I would opt for a different manufacturer.

You said they are 50 watt GU10's, so I would assume they are 120V halogens, and you must simply have gotten a bad dimmer. But if these GU10's are 50 watt equivalent (LED's or CFL's) then the bulbs will have their own transformers built into them, and would be incompatible with a dimmer switch. It also might be the case that you have low voltage halogens which would use a transformer, shared or individual, and these would also be incompatible with a dimmer. (I don't know offhand if GU10's are available with low voltage halogens.)

If each pendant has an individual transformer that is about the size of a hotwheel then you need a dimmer specifically for ELECTRONIC LOW VOLTAGE. A lot of electricians don't know that the different types of lights require different dimmers. Most store bought dimmers are for incandescent lights only, and some nicer dimmers like the Lutron Maestro's are rated for incandescent or MAGNETIC Low Voltage which require a different Sin wave interuption. I don't know that leviton makes a dimmer in that style for Electronic Low Voltage. You could install a Lutron DVELV300P-Wh, but that is a Decora opening. http://www.lutron.com/CMS400/WorkArea/downloadasset.aspx?id=25437
Here is a link to explain the difference in how the dimmer needs to work. Good luck!

Unfortunately, the hum is normal for operation of that type of dimmer at low levels.  Sometimes the lamp filaments will also "sing" a high pitched sound.